Thursday Throughput: Gamma-ray Bursts Are Bad Edition


Michael Siegel

Michael Siegel is an astronomer living in Pennsylvania. He is on Twitter, blogs at his own site, and has written a novel.

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10 Responses

  1. Avatar DensityDuck says:

    If the culture becomes “publish your data even if there’s a null result”, this is one of the ways that I would actually accept “this research was funded by EvilBigCo Incorporated” as a criticism; because if EBCINC wants the study to show a link between mothers drinking EBCINCola and higher IQ in babies, and the study doesn’t show that, then they’d have a strong incentive to throw the data out and claim that it was never “really” studied…Report

  2. Avatar Oscar Gordon says:

    Mining such an asteroid wouldn’t really crash markets, since even if we moved it into a nearby orbit, mining would take time. What would happen is that low margin mines on earth would be at risk of shutting down unless we started finding ways to use up those new space based resources (such as using the materials to build habitats and ships).Report

    • Not just time, the cost of retrieval even from high orbit. Consider what it costs to put up a vehicle capable of bringing down a few tons of cargo safely (both for the cargo and for the planet). Truly rare stuff might be worth it. OTOH, the value of a few million tons of steel (a tiny fraction of the asteroid’s mass) in high orbit will inevitably be due its position, and bringing it down would almost certainly decrease its value.Report

      • Avatar Oscar Gordon in reply to Michael Cain says:

        Depends on the intended purpose. Get things down a gravity well is pretty easy, as long as you intend for it to stay at the bottom of the well. If it has to go down and back up again, then that is just silly. Keep it up there and figure out how to process it in situ.

        Of course, that adds to the time factor. Even if we captured that monster and got it close to Earth, and started to mine it, we’d have to develop ore processing facilities in space, unless we fully intended every kg to be used on Earth. Which, again, is kinda silly, given that we have lots of mining on Earth. Mining that thing for use down here is only going to make sense if the cost of mining a given mineral on Earth exceeds the cost of sending men and machines to the asteroid.

        So yeah, a rock like that isn’t going to be upsetting markets at home any time soon, and the very act of developing the technology to extract resources from that rock will mean that we’ll probably be putting the products to use up there way more than we will down here.Report

    • Avatar North in reply to Oscar Gordon says:

      Yeah, there’s nothing quite like talking about space based metal asteroids to demonstrate emphatically how you can be a fishing brilliant scientist in one field and not know a god(ess?)damn thing about economics.

      Somehow capturing a massive metal rich asteroid in earth orbit wouldn’t be an economic disaster- it’d be an economic bonanza. The enormous decrease in the costs of metal would be accompanied by a decreasing cost in the products that use those metals and a plethora of new uses for those metals. Mining those metals in space instead of sullying our Terran eco-sphere with mines would also be an enormous boon both economically and environmentally. And, let’s be real, the only way we’re going to do much of anything major in space is if we start making stuff up there. Hauling shit up out of the Terran gravity well is just insanely expensive.Report

  3. Avatar Aaron David says:

    Fun fact: My father’s dissertation was on the effects of gamma rays on the genetic structure of African Violets.Report

  4. Avatar George Turner says:

    ThTh2: Image a one meter empty cube whose only contents were from quantum fluctuations. Imagine another one meter cube filled with all the times ground-based astronomy has won battles against enormous commercial interests. How can you distinguish the mass difference between the two cubes?

    ThTh7: I once came up with a way to get from LEO to the moon with no mass expenditure at all, though I’m probably not the first to think of it. You put up two satellites in opposite orbits (one retrograde) and use a high-velocity rail gun to fire a slug to produce an impulse (the recoil is the thrust). The muzzle velocity of the gun is made to be exactly twice the orbital velocity, plus the small delta V it gives to the satellite. You fire the slug as the two satellites pass each other, and every time they cross they find that the other satellite’s slug is floating right alongside them, following the same orbit (+V -2V = -V, and -V +2V = V). So each grabs the other’s slug and reuses it.

    Even though the the satellites are making constant transfer orbits, stepping their way higher and higher, the orbital math works out exactly. The trip time is limited by the delta-V per pass, and increases linearly with the number of satellites in the constellation. Using 20 satellites, 10 in each of the two orbits, lets them exchange 10 times as many slugs per orbital revolution, and thus move upwards 10 times faster.

    Of course as the constellation goes higher, the orbital velocity decreases (as does the required muzzle velocity), but the number of exchanges per hour also drops, such that the technique is only very useful down in deep gravity wells. If you were trying to get to outer planets, and each exchange gave you a 50 m/sec delta V, you’d get 100 m/sec acceleration per year, and you’d need another satellite in retrograde orbit around the sun, and if you can put a satellite in that crazy retrograde orbit you wouldn’t be playing around with a cheesy slug-transfer propulsion method.

    And of course the snag is coming up with a magnetic gun with sufficient muzzle velocity.Report

    • “hTh2: Image a one meter empty cube whose only contents were from quantum fluctuations. Imagine another one meter cube filled with all the times ground-based astronomy has won battles against enormous commercial interests. How can you distinguish the mass difference between the two cubes?”

      Astronomers have won multiple battles on light pollution — both optical and radio.Report

      • Avatar George Turner in reply to Michael Siegel says:

        But did it cost any real commercial money, or did it just create an excuse for a city to spend more money on a more expensive lighting product? Or take Greenbank West Virginia. How many billions a year in income did they have to forgo?

        I really see no chance that astronomers will win against giant satellite constellations that will easily generate tens of billions in revenue and provide Internet access to rural African or Indian villages so they can get vital medical information.Report